A spatiotemporal analysis of cattle herd movement in relation to drinking-water sources: implications for Cryptosporidium control in rural Kenya

Environmental Science and Pollution Research https://doi.org/10.1007/s11356-021-17888-3 RESEARCH ARTICLE A spatiotemporal analysis of cattle herd movement in relation to drinking-water sources: implications for Cryptosporidium control in rural Kenya Jessica R. Floyd1 · Emmah Kwoba2 · Thumbi Mwangi2 · Joseph Okotto‑Okotto3 · Peggy Wanza2 · Nicola Wardrop1 · Weiyu Yu1 · Jim A. Wright1 Received: 24 March 2021 / Accepted: 27 November 2021 © The Author(s) 2021 Abstract Given the increasing evidence that domestic contact with livestock is a risk factor for child diarrhoea in low- and middleincome countries, there have been calls for greater quantification of human-livestock contact in such countries. This study aimed to quantify seasonality in cattle proximity to domestic water sources and household compounds and develop a preliminary landscape model of faecal deposition by cattle. A total of 120 cattle in smallholder herds in the Asembo area of Siaya County, Kenya, were tracked over 1 week in April 2018 to July 2018 and November 2018 to February 2019 using GPS tracking devices. Dung deposition and behaviour were observed among 33 cattle from these herds over 185.4 hours. Mean cattle home ranges were small at 3.78 km2 and 5.85 k m2 in the wet and dry seasons, respectively. There were significant differences between seasons in home range size, distance travelled from the household, and time spent tethered, but not in the time spent at domestic water sources or home range overlap with other herds. On average, 0.76 dung deposition events/hour were observed, with higher frequency in bulls. Variation in cattle proximity to household compounds and water sources did not account for seasonal variation in child diarrhoea in this population. The preliminary landscape model of faecal deposition by cattle could be further developed to inform interventions for safe separation of livestock and people, such as fencing and separate water troughs. Keywords Cryptosporidium · Landscape · Kenya · Livestock · Animal movement · Water contamination Introduction Diarrhoeal disease is the second highest cause of death in children under 5 worldwide, killing over half a million under-fives each year (“WHO | Diarrhoeal disease,” 2017). Responsible Editor: Philippe Garrigues * Jessica R. Floyd 1 School of Geography and Environmental Science, University of Southampton, Building 44, Highfield, Southampton SO17 1BJ, UK 2 Centre for Global Health Research, Kenya Medical Research Institute, P.O. Box 1578‑1400, Kisian campus, Kisumu‑Busia Highway, Kisumu, Kenya 3 Victoria Institute for Research on Environment and Development (VIRED) International, P.O. Box 6423‑40103, off Nairobi Road, Rabuor, Kenya Since several common diarrhoea pathogens (e.g. campylobacter, salmonella, and Cryptosporidium spp.) are harboured by animals as well as humans, there is growing evidence implicating livestock in diarrhoea transmission. Systematic review evidence (Zambrano et al. 2014) found a positive association in almost all included studies examining pathogen-specific diarrhoea in relation to animal husbandryrelated risk factors. This has led to calls for greater understanding of potential transmission pathways via soil, hands, flies, fomites (i.e. objects such as utensils or toys likely to carry infection (Penakalapati et al. 2017)), and fluids including from water sources. Among diarrhoeal pathogens infecting humans and livestock, the genera Cryptosporidium are common enteric parasites that cause significant morbidity and mortality via a diarrhoeal infection known as cryptosporidiosis (Checkley et al. 2015). The Global Enteric Multicentre Study (GEMS) identified Cryptosporidium as one of four pathogens to which most cases of moderate to severe diarrhoea (MSD) 13 Vol.:(0123456789) Environmental Science and Pollution Research were attributable (Kotloff et al. 2013). Cryptosporidium transmission occurs through shedding of parasite oocysts in host faeces, which are immediately infective and can be ingested by other hosts through contaminated food and water. The infective dose is so low that just one oocyst is enough to cause an infection, and they are remarkably resistant to degradation: oocysts can survive for as long as 6 months suspended in water, and are also resistant to common chemicals used in water treatment (Smith et al. 2006). Moreover, some species like C. parvum can infect multiple host species, including humans and livestock, and have been responsible for previous waterborne outbreaks. This includes the largest waterborne disease outbreak in US history, which caused 403,000 cases in Milwaukee in 1993 (Kramer et al. 1996) as well as other outbreaks related to drinking water contamination (Glaberman et al. 2002). Although it can be difficult to prove the original source of an outbreak, water contamination by domesticated animals or livestock is widely recognised as a significant public health hazard (Graczyk et al. 2000). Thus, livestock are known to be a source of both direct infection and environmental contamination. These qualities make elimination of Cryptosporidium oocysts in the environment very difficult, and with research into a vaccine still ongoing (Checkley et al. 2015; Ryan and Hijjawi 2015), evidence is needed to support environmental interventions that may reduce the transmission of oocysts from cattle to humans. This is a particular priority in those populations that are still drinking from untreated surface waters, the bottom ‘rung’ of the WHO/UNICEF Joint Monitoring Program (JMP) ladder (WHO/UNICEF 2017). In terms of seasonal patterns, a global meta-analysis suggested that in sub-Saharan Africa, cryptosporidiosis peaks follow periods where satellite-derived vegetation indices are low (Jagai et al. 2009). In Kenya nationally, analysis of hospitalised cases suggests that cryptosporidiosis peaks in the driest November–February period (Gatei et al. 2006), whilst in Meru, Kenya, recovery of Cryptosporidium oocysts from surface waters was greatest in the late rainy season and early dry season (Muchiri et al. 2009). However, there is little evidence on how seasonal variation in contact between humans and livestock compares to such seasonal variation in cryptosporidiosis. Previous studies have used geospatial data to estimate the spatial pattern of cryptosporidium in the landscape at the population level (Burnet et al. 2014; Kato et al. 2004), but this has not been done at the micro scale level using data concerning individual animals. In wildlife ecology, it is common to collect data on individual species via tracking technology such as GPS collars and radio telemetry (Naidoo et al. 2012; Trivelpiece et al. 1986). However, to date, there have been no such individual-level studies that have applied this technology to ‘one health’ problems that entail 13 pathogen movement between livestock and people via the environment. In this study, we seek to address this gap by using GPS trackers to quan (...truncated)